Method of casting



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WILLIAIVZ C. BOWERS, 0F NEWARK, NEW JERSEY, ASSIGNOR TO AMERICAN ABRASIVE METALS COMPANY, OF NEW YORK, N. Y., A. CORPORATION OF NEW YORK.

METHOD 01E CASTING.

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No Drawing.

To all whom it may concern:

Be it known that 1, WILLIAM C. Bownns, a citizen of the United States, residing at Newark, in the county of Essex and State of New Jersey, have invented certain new and useful Improvements in Methods of Casting, of which the following is a specification. This invention relates to the manufacture of metal castings having a protective or wear-resistant surface, such as in stair treads, floor plates, trench or gutter covers and the like, wherein bodies or particles of hard wear-resistant material are embedded in a metal body or casting .so as to'be exposed on the surface thereof; and my invention consists of an improved, simple and effective method of castingby which the hard wear-resistant bodies or'particles will become firmly fixed and embedded in the process ofcasting, and will form on the face of the same a protective wear-resistant surface. In carrying my method into practice in the preferred manner of procedure, 1 provide a suitable mold usually of green sand, and coat the mold surface which is to give form to the protective surface of the casting, with a layer of material in finely divided or powdered form, which may be applied by sprinkling the material over said surface so as to form a receiving or holding bed for the particles of resistant material.

On this bed I distribute the particles of resistant material which are to form the protective or wear resisting face of the casting, which resistant material may be either corundum, carborundum, alundum, or other hard mineral wear-resistant substances, or metals which will not fuse at the temperature of molten iron. With the two materials.

applied and distributed in this manner, the particles of the resistant material will be heldby the bed from any substantial displacement when the molten metal is poured into the mold. Finally the molten metal, usually cast iron, is poured into themold, with the result that the particles of resistant material held from displacement by the bed, willbe surrounded by and embedded in the metal of the casting and will form a wear-resistant surface thereon.

Various materials for forming the holding bed may be employed, but I prefer to use either an infusible mineral substance, such as powdered fire clay, infusorial earth, etc., or a material which will become con- Specification of Letters Patent.

Patented J an. it), 1922.

Application filed May 23, 1919. Serial No. 299,333.

metal, such for instance as rye flour, powdered asphalt, core compounds, etc. I select mater1alspossessing these particular characteristics, for the reason that they will have no effect or influence on the surface of the sumed or dissipated by the heat of molten casting, as the first, variety, the infusible use of materials possessing the particular characteristics mentioned as other materials may be vused to advantage.

When the holding material infinely divided or powdered form is applied to the surface ofa mold composed of reen sand, .as above described, the dry materlal will absorb the moisture from the mold, which will cause the bedto efiectually hold the wear-resistant particles against substantial displacement by the flow of the molten metal, and in the casting operation, the hard particles will be surrounded and embedded in the metal of the casting at its surface.

By the use of a material in finely divided or powdered form as a holding bed for the wear-resistant particles, it will when applied to the surface of a green sand mold adhere thereto by reason of the moist character of the mold surface, and consequently the material can be readily applied to vertical core surfaces and irregularly shaped and overhanging surfaces. I

My improved method is applicable to the casting of articles of various forms and shapes designed for various'uses where it isdesired that the article will have a protective surface which will resist abrasion or wear, more particularly stair treads, floor plates and the like, to prevent the feet from slipping.

l/Vhile I have particularly described in the carrying out of my improved method, the use of the materials in finely powdered or comminuted form, it is manifest that they may be employed in other and coarser forms, more particularly the wear-resistant material, according to,. the character of the article it is intended to produce and the use p for which it is to be employed.

By forming the holding bed or layer in the mold of greater or less thickness, the

method consists in varied, which will correspondingly vary the character of the protective 'face, acoarser surface being produced when the bed in the,

mold is thick and permits the particles to sink deeper therein, and a finer surface being produced when the bed is thinner and exposes the the grip of the metal of the casting.

After the holding bed or layer has been applied in powdered form to the mold surface as above mentioned, 'it may be sprinkled with a liquid, preferably water, either before or after the particles of wear-resistant material have been distributed thereon, with the result that the protective surface will be of a finer texture.

It will be manifest that in the practice of my method of casting, greater or less portions of the mold surface may be covered with the holding material, according to the extent, form and location which it is desiredthat the ing will have. a r

Having thus described my invention, what I claim is:

1. The method of forming metal castings having a wear-resistant surface, which providing a mold, apply- 1ng to the mold surface which is'to give form to the wear-resistant surface of the casting, a layer composed of disunited particles of holding material to form a loose bed for the wear-resistant materials, disprotective surface of the casttributing particles of a wearresistant material over said-bed and causing them to partially embed themselves therein, and finally introducing molten metal into the mold.

2. The methodof forming metal castings having a wear-resistant surface, which method consists in providing a mold, applying to the mold surface which is to give form to the wear resistant-surface of the casting, a layer composed of disunited particles of holding material to form a loose bed for p the wear-resistant material, distributing particles ofva wear-resistant material over said bed and causing them to parparticles to a greater degree to tially embed themselves therein, and finally introducing molten metal into the mold, the holding material being of a character which on contact with the molten metal will not coalesce or fuse therewith.

' 3. The method of forming metal castings infusible mineral substance so as to form a bed for the wear-resistant material, distributing particles of the wear-resistant material over said bed, and finally introducing moltenmetal into the mold.

4- The method of'forming metal castings having a wear-resistant surface, which method consists in providing a mold, sprinkling an infusible material in powdered form over the mold surface which is to give form to the Wear-resistant surface of the casting so as to form a holding bed for the wear-resistant material, distributing particles of a hard wear-resistant material over the bed, and finally introducing-molten metal into the mold. 7

5. The method of forming metal castings havingv a 1 wear-resistant surface, which method consists in providing a mold, apply.- ing to -the mold surface which is to give form to the wear-resistant surface of the casting, a layer of holding material in powdered form to constitute a bed for the wearresistant material, distributing particles of a wear-resistant material over the bed, sprinkling said bed with a liquid, and finally introducing molten metal into the mold.

6. In the method of forming metal castingshaving a Wear-resistant surface, pr viding a mold, applying to the mold surface which is to give form to the wear-resistant surface of the casting, a layer of material in powdered form to hold the Wear-resistant particles, and sprinkling adiquid over said material.

In testimony whereof, I have aflixed my signature hereto.

WILLIAM C. BQWERS. 

